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Capacity unbalance is a practical problem for future cellular networks where the forward link traffic and the reverse link traffic are asymmetric. In this paper, an analytical framework for balancing the reverse and forward link capacities with an adaptive soft handoff probability (SHP) scheme in multiservice code-division multiple-access cellular networks is presented. With the proposed adaptive SHP scheme, system capacity can be balanced under various reverse and forward link traffic volumes, and system performance is optimized at the optimal SHP. A cross-layer model involving the physical layer, the link layer, and the network layer is presented. SHP in the physical layer, the outage probability in the link layer, and connection admission control (CAC) schemes, including complete sharing and virtual partitioning, in the network layer are jointly considered. The quality of service metrics in the link layer, including SIR and the outage probability, is derived with the information from the physical layer. The admission region is obtained by satisfying the outage probability requirements in both the forward and reverse links. Based on the admission region, the network layer grade of service, including the new connection blocking probability, the handoff connection dropping probability, and the throughput, is formulated as the performance metrics. The optimal SHP is selected by looking for the lowest penalty of connection blocking, which counts in both new connection blocking and handoff connection dropping probabilities. The cross-influences between the selection of the optimal SHP and the CAC schemes are also investigated. Numerical results show that the maximum achievable gain in throughput for the high-revenue services is about 80% by combining the benefits from the adaptive SHP and dynamic CAC schemes as compared to when none of these schemes is used

A freestanding rigid body under the action of base excitation can move in many different ways. In this study, the sliding response of a body is considered. The body is placed on a horizontal base that undergoes a one-dimensional horizontal motion. In 1965, Newmark (1965) gave a simple formula to determine the sliding distance of a freestanding body subjected to a single rectangular acceleration pulse of short duration at the base. The objective of this study is to see if this formula can be applied to estimate the sliding displacement of a body under the action of real earthquakes. Newmark's formula calls for the maximum velocity of the base which information is usually not directly available. To make use of the response spectrum commonly available to the engineers, Newmark's formula is first re-derived and expressed in terms of the maximum displacement of the base, which can be determined from the absolute displacement response spectrum in low frequency range. An ensemble of 75 real earthquakes is then employed, the equation of sliding motion is solved numerically and the average of the maximum sliding displacement of the body relative to the base is computed. The computed displacement is then compared with that obtained by Newmark's formula. This is done for a body placed on the ground as well as on the floors of a building. It is shown that Newmark's formula can be used if an adjustment factor, as suggested in this study, is applied. Key words: earthquake, sliding, unanchored body

In this paper, we propose a dynamic bandwidth control based medium access control (DBC-MAC) protocol for CWPAN/IEEE 802.11aj networks, which consists of operations like network establishment, network termination, channel splitting and channel expansion. The proposed DBC-MAC protocol solves the coexistence problem between CWPAN/IEEE 802.11aj networks and IEEE 802.11ad networks that are operating in the same or overlapping 60 GHz band and also supports the backward compatibility with the legacy IEEE 802.11ad stations. Performance evaluations show that the DBC-MAC protocol under CWPAN/IEEE 802.11aj networks outperforms the fixed channel bandwidth mechanism under IEEE 802.11ad networks for specific performance metrics.

Species of Clostridium bacteria are notable for their ability to lyse tumor cells growing in hypoxic environments. We show that an attenuated strain of Clostridium novyi (C. novyi-NT) induces a microscopically precise, tumor-localized response in a rat orthotopic brain tumor model after intratumoral injection. It is well known, however, that experimental models often do not reliably predict the responses of human patients to therapeutic agents. We therefore used naturally occurring canine tumors as a translational bridge to human trials. Canine tumors are more like those of humans because they occur in animals with heterogeneous genetic backgrounds, are of host origin, and are due to spontaneous rather than engineered mutations. We found that intratumoral injection of C. novyi-NT spores was well tolerated in companion dogs bearing spontaneous solid tumors, with the most common toxicities being the expected symptoms associated with bacterial infections. Objective responses were observed in 6 of 16 dogs (37.5%), with three complete and three partial responses. On the basis of these encouraging results, we treated a human patient who had an advanced leiomyosarcoma with an intratumoral injection of C. novyi-NT spores. This treatment reduced the tumor within and surrounding the bone. Together, these results show that C. novyi-NT can precisely eradicate neoplastic tissues and suggest that further clinical trials of this agent in selected patients are warranted.

Intra-articular injection of streptococcal cell wall Ag followed by i.v. challenge (“reactivation”) results in a destructive lymphocyte-dependent monoarticular arthritis. To further define the role of immune mechanisms in the model, Abs to Th1 and Th2-related cytokines were evaluated. Treatment of rats with antibodies to IL-4 reduced swelling, while treatment with anti-IL-10 or anti-IFN-γ either had no effect or slightly enhanced the inflammatory response. These results suggest that Th-2 immune mechanisms may be, at least in part, operative in the model. To more precisely define the role of IL-4, the effects of anti-IL-4 on monocyte chemoattractant protein-1 (MCP-1) expression were evaluated. Initial studies demonstrated that mRNA (as determined by in situ hybridization) and protein (as determined by immunofluorescence) for MCP-1 were detectable in inflamed synovial tissue in a time-dependent manner. Anti-IL-4 treatment significantly reduced the expression of mRNA for MCP-1 24 and 72 h after reactivation. In addition, anti-MCP-1 inhibited swelling and reduced influx of 111In-labeled T cells. These data suggest that the reactivation model of streptococcal cell wall Ag-induced arthritis is Th-2 dependent, and that an inter-relationship exists between IL-4 and the expression of MCP-1.

B Purpose: This study aimed to investigate the effects of surface and shoe cushioning on the metabolic cost of running. In running, the leg muscles generate force to cushion the impact with the ground. External cushioning (surfaces or shoes) may reduce the muscular effort needed for cushioning and thus reduce metabolic cost. Our primary hypothesis was that the metabolic cost of unshod running would decrease with a more cushioned running surface. We also hypothesized that because of the counteracting effects of shoe cushioning and mass, unshod running on a hard surface would have approximately the same metabolic cost as running in lightweight, cushioned shoes. Methods: To test these hypotheses, we attached 10- and 20-mm-thick slats of the same foam cushioning used in running shoe midsoles to the belt of a treadmill that had a rigid deck. Twelve subjects who preferred a midfoot strike pattern and had substantial barefoot/minimalist running experience ran without shoes on the normal treadmill belt and on each thickness of foam. They also ran with lightweight, cushioned shoes on the normal belt. We collected V[spacing dot above]O2 and V[spacing dot above]CO2 to calculate the metabolic power demand and used a repeated-measures ANOVA to compare between conditions. Results: Compared to running unshod on the normal belt, running unshod on the 10-mm-thick foam required 1.63% +/- 0.67% (mean +/- SD) less metabolic power (P = 0.034) but running on the 20-mm-thick foam had no significant metabolic effect. Running with and without shoes on the normal belt had similar metabolic power demands, likely because the beneficial energetic effects of cushioning counterbalanced the detrimental effects of shoe mass. Conclusions: On average, surface and shoe cushioning reduce the metabolic power required for submaximal running.

Doxazosin is an α(1)-adrenergic receptor antagonist for the treatment of high blood pressure and benign prostatic hyperplasia. Peripheral α-adrenergic receptors have been implicated in inflammation.To examine the anti-inflammatory effects of doxazosin in rodent models of inflammation.The anti-inflammatory properties of doxazosin were investigated in 4 models. In all studies, drug treatment was administered 15 min prior to challenge. In the lipopolysaccharide (LPS)-induced systemic inflammation model, LPS was injected systemically at 0.25 mg/kg. At 90 min after challenge, blood samples were collected for analysis. In the LPS-induced pulmonary inflammation model, LPS was instilled intranasally. Four hours after challenge, the lungs were harvested for monocyte chemoattractant protein-1 (MCP-1) analysis. In a delayed-type hypersensitivity model, the mice were injected intravenously with sheep red blood cells, and rechallenged in the left footpad 7 days later. Drug treatment was given on day 6 and 7 just prior to the rechallenge. The thickness of hind footpads was measured at 15 min after rechallenge. In the thioglycollate-induced peritoneal monocyte infiltration model, mice were challenged with 3% thioglycollate, and 2 h later peritoneal lavage fluid was collected for MCP-1 analysis.In animals challenged systemically and intranasally with LPS, doxazosin inhibited TNF-α and MCP-1 production, respectively. In the delayed-type hypersensitivity model, footpad swelling was inhibited by doxazosin. Doxazosin decreased the level of MCP-1 release in the peritoneal cavity of thioglycollate-stimulated animals, though this effect was not statistically significant.This is the first set of studies that reports the novel anti-inflammatory effects of doxazosin.

Radiolabeled ubiquitin was introduced into HeLa cells by red cell-mediated fusion procedure. The nuclei contained two major labeled proteins, ubiquitin and protein A24. The cytosol contained ubiquitin and a series of ubiquitin-protein conjugates. When the cotransferred hemoglobin was denatured by phenylhydrazine, a series of prominent ubiquitin-globin conjugates appeared. The concentration of globin-ubiquitin conjugates was proportional to the rate of hemoglobin degradation. These results provide support for the hypothesis that the covalent attachment of ubiquitin to proteins signals proteolysis. However, direct ubiquitin attachment to substrates does not appear to be mandatory for proteolysis. Guanidinated (G) proteins, which have blocked lysine residues, were used as potential substrates for ATP-dependent proteolysis in rabbit reticulocyte lysates. G-lysozyme was degraded by an ATP-dependent process, yet ubiquitin conjugation to this protein was not observed. In contrast, conjugates between ubiquitin and lysozyme were readily detected. A ubiquitin-free fraction of the lysate was obtained which degraded both G-lysozyme and lysozyme by an ATP-dependent process that was stimulated by ubiquitin. Neither ubiquitin nor ATP alone significantly stimulated the formation of labeled adducts in ubiquitin-free lysates incubated with the labeled proteins. When both ubiquitin and ATP were added to the reaction mixtures, G-lysozyme-ubiquitin conjugates were not observed; whereas, lysozyme-ubiquitin conjugates were readily detected. These observations cast doubt on the hypothesis that ubiquitin has a unitary role as a covalent marker in ATP-dependent proteolysis.

A good approximate analytical formulation of the saturated throughput of a Cooperative MAC (CoopMAC) is presented via a two-dimensional discrete-time Markov chain rather than using an approximation. A helper node is used to relay packets from the source node to the destination node within a coverage via a faster two-hop link if possible. The analytical model is formulated with a number of data rates and their corresponding distances. The critical probabilities that at least a helper node exists in different regions to relay packets are explicitly derived through areas of the intersection of the coverages of the source and destination nodes using different data rates to the helper node. By using the weighted sum of the probabilities of the statistics of each of the stations, the saturated throughput of CoopMAC protocol is explicitly derived. Numerical results of the saturated throughput show that the agreement between the simulation and the new analytical results for CoopMAC is very good.

Background: Repaglinide is an FDA-approved treatment for type 2 diabetes mellitus. The anti-inflammatory effect of repaglinide in the absence of diabetes has not been reported previously. It is the objective of this set of studies to investigate the potential anti-inflammatory effects of repaglinide. Method: The in vivo anti-inflammatory effects of repaglinide were studied in two different models of delay type hyperreactivity (DTH) response induced by sheep red blood cells (sRBC) and 2,5′-dinitrofluorobenzene (DNFB), and in two different rodent models of lipopolysaccharide (LPS) challenge. Results: In mice systemically sensitized with sRBC, which subsequently received a local injection of sRBC in the footpad, local swelling occurred within 24 h after challenge. Repaglinide was efficacious in attenuating this response. In an orthogonal DTH model using DNFB as the antigen, the animals received topical sensitization with DNFB on their shaved backs, followed by topical challenge on the left ears. Repaglinide efficaciously downregulated the resulting ear swelling response. In mice challenged systemically or intratracheally with LPS, repaglinide significantly decreased serum tumor necrosis factor α level and bronchial alveolar lavage fluid MCP-1 levels, respectively. Conclusion: This set of data suggests novel anti-inflammatory effects of repaglinide in nondiabetic animals. However, the high dose required for an efficacious effect would make this application impractical in the clinic.

Analytical formulations of the throughput of multi-channel medium access control (MAC) protocols are presented. Both multi-channel multi-rate MAC and multi-channel CoopMAC protocols are considered. A discrete time Markov chain is used to model the number of nodes communicating with the AP in the multi-channel multi-rate MAC protocol, while another discrete time Markov chain is used to model the number of data channels used in the multi-channel CoopMAC protocol. The throughput of the multi-channel multi-rate MAC protocol is expressed as a function of the number of data channels, the channel transmission rate and the solutions to the first Markov chain, while the throughput of the multi-channel CoopMAC protocol is expressed as a function of the number of data channels, the channel transmission rates, and the solutions to the latter Markov chain. The first Markov chain only considers direct one-hop links communications in the multi-channel multi-rate MAC, while the latter Markov chain accounts not only the direct one-hop links communications but also for faster two-hop relaying links communications in the multi-channel CoopMAC as well. Numerical results of the throughput corresponding to typical values are presented. The results also clearly demonstrate the advantage of our proposed multi-channel CoopMAC protocol over a multi-channel multi-rate MAC protocol.

In our paper, we propose a Multi-Rate IEEE 802.11b MAC protocol with network coding. The standard X-OR operation is used in the network coding. Two topologies of paired topology and random topology are considered. The analytical framework is formulated for n stations. The state transition diagram is modeled by a two-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage and the second dimension is for the value of the backoff counter. The saturated throughputs are formulated by nested summations of saturated throughputs. Numerical results of the saturated throughput corresponding to typical parameter values are presented. These results show the advantage of the proposed Multi-Rate IEEE 802.11b MAC protocol with network coding over a basic IEEE 802.11b MAC protocol using RTS/CTS access method. Our new analytical formulations of the saturated throughputs of these MAC protocols can be used even for a small number of stations.

The maximum throughput is limited by the slowest transmitting station in IEEE 802.11 distributed coordination function (DCF) medium access control (MAC), giving rise to the rate anomaly problem. This limitation is carried into a cognitive IEEE 802.11b DCF MAC. In our paper, we propose airtime fairness in a cognitive rate separation IEEE 802.11b MAC. Stations are grouped according to their transmission rates for transmitting their packets in different data transmission periods (DTPs) for the different groups of stations. A sensing period is used to sense for primary transmissions. The analytical framework is formulated for N stations, including an access point (AP). The state transition diagram is modeled by a two-dimensional discrete-time Markov chain. The saturated throughput is approximated by the sum of the product of a weighted ratio of the throughput of the DTP under consideration and the throughput of the DTP minus the period necessary to transmit a packet before the end of the current DTP, the probability of the number of devices in the DTP, the number of DTPs and the probability of false alarm. The DTPs to achieve airtime fairness are formulated as non-linear equations, which are solved using Newton-Raphson method with Jacobian functions. Numerical results of the saturated throughput corresponding to typical parameter values are presented. The advantage of the proposed cognitive rate separation IEEE 802.11b MAC with airtime fairness is shown through achieving airtime fairness and high saturated throughput.

We consider a distributed opportunistic spectrum access (D-OSA) scenario in which multiple cognitive radio (CR) users attempt to access a channel licensed to some primary network. CR users operate on a frame-by-frame basis and need to carry out spectrum sensing at the beginning of each frame to determine whether the primary network is active or idle. Upon detecting the primary network being idle, CR users employ distributed/random-access mechanisms to transmit data. Spectrum sensing is imperfect and introduces false alarms and mis-detections. To protect primary users, it is required that the combined probability of mis-detection of all CR users must be below a specified threshold. For this, we argue that a cross-layer approach that jointly controls PHY-layer spectrum sensing and MAC-layer random access achieves significant gain in the saturated throughput of CR network. Our approach is motivated by an insightful observation, i.e., without compromising primary-user protection, allowing CR users to carry out spectrum sensing at a relatively high probability of false alarm achieves the dual benefits of reducing time spent on spectrum sensing and reducing throughput loss due to random-access collisions. Numerical results are presented to illustrate our approach.

Osteoarthritis (OA) is a degenerative joint disease that has no FDA-approved treatment. The current standard of care does not address the regeneration of the damaged cartilage. Human growth hormone (hGH) is part of the insulin-like growth factor (IGF)-1 axis. There has been preclinical data that suggest its potential regenerative property in the joint. However, unformulated recombinant hGH (rhGH) is short-lived in the joint, and does not provide a desirable pharmacokinetic (PK) profile to support a clinical treatment paradigm. Polyethylene glycol (PEG)ylation is a potential method to extend the half-life of rhGH in the joint. The purpose of this study was to delineate the PK/PD profile of PEG-rhGH in the knee joint in a rat preclinical model of OA. After intra-articular (IA) injection of 100 microg into a rat knee joint that underwent medial meniscectomy, PEG-rhGH exhibits 2-fold longer half-lives in joint than native hGH. However, PEG-rhGH has a much longer systemic exposure. IA injections of PEG-rhGH also resulted in higher levels of IGF-1 in the joint and serum when compared with native rhGH. In order to develop PEG-rhGH as an IA therapeutic treatment for OA, careful dose selection is necessary to avoid systemic effects while retaining its anabolic efficacy in the joint.

IEEE 802.11 distributed coordination function (DCF) medium access control (MAC) does not provide airtime fairness for all stations in a multi-rate scenario as it only provides max-min throughput fairness. This gives rise to the rate anomaly problem where the maximum throughput is limited by the slowest transmitting station. In our paper, we propose airtime fairness in a rate separation IEEE 802.11b MAC. Stations are grouped according to their transmission rates for transmitting their packets in different data transmission periods (DTPs) for the different groups of stations. The analytical framework is formulated for N stations, including an access point (AP). The state transition diagram is modeled by a two-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage and the second dimension is for the value of the backoff counter. The saturated throughput is approximated by the sum of the product of a weighted ratio of the throughput of the DTP under consideration and the throughput of the DTP minus the period necessary to transmit a packet before the end of the current DTP, the probability of the number of devices in the DTP and the number of DTPs. The DTPs to achieve airtime fairness are formulated as non-linear equations, which are solved using Newton-Raphson method with Jacobian functions. Numerical results of the saturated throughput corresponding to typical parameter values are presented. These results show the advantage of the proposed rate separation IEEE 802.11b MAC with airtime fairness in achieving airtime fairness and high saturated throughput.

An analytical formulation of the mean detection time and the distribution of the detection time of a wireless microphone (primary user) in an IEEE 802.22 wireless regional area network (WRAN) is presented. The IEEE 802.22 WRAN has a number of customer-premises equipments (CPEs) in the coverage area of its base station. Out of this number of CPEs, a number of them are within the coverage area of the microphone. All of the CPEs can be inactive or active. This is modeled by a discrete time Markov chain. If the microphone turns on or becomes active, the WRAN must be able to detect the microphone and vacates the channel within a time threshold. It is assumed that as long as one of the active CPEs, within the coverage area of the microphone, detects the microphone as active, the microphone is detected. The mean and the distribution of the detection time of the microphone are derived by modeling the detection time by an absorbing discrete time Markov chain. Numerical results corresponding to typical parameter values are presented. The tradeoffs among the number of CPEs, coverage range of the wireless microphone (primary user) and probability of detection are investigated.

This paper considers a distributed opportunistic spectrum access (D-OSA) scenario in which multiple cognitive radio (CR) users attempt to access a channel licensed to some primary network. CR users operate on a frame-by-frame basis and need to carry out spectrum sensing at the beginning of each frame to determine if the primary network is active or idle. Upon detecting the primary network being idle, each CR user employs a modified 802.11 DCF protocol for contention-based channel access. Spectrum sensing is imperfect and introduces false alarms and mis-detections. To protect primary users, it is required that the combined probability of mis-detection of all CR users must be below a specified threshold. We provide concrete protocol design, performance analysis, and extensive simulation results for our D-OSA design. Our results highlight the importance of taking a cross-layer view and jointly designing PHY-layer spectrum sensing and MAC-layer channel access.

An analytical formulation of the dynamic spectrum allocation problem for handling multiclass services in two cellular radio systems using a complete sharing (CS) scheme is presented. A CS scheme with multiple guard channels for giving prioritization of radio system 1psilas new and handoff call connection over those of radio system 2 and giving prioritization of handoff connections over new connections in each radio system is used for the resource sharing policy at the connection level. The CS model is solved using a K-dimensional Markov chain. Numerical results are illustrated to show the performance of this scheme. The performance metrics include new and handoff connection blocking probabilities and system utilization.

We consider a scenario in which a secondary user makes opportunistic use of a channel allocated to a primary network. The primary network operates in a time-slotted manner and switches between idle and active states according to a stationary Markovian process. At the beginning of each time slot, the secondary user can choose to stay idle or to carry out spectrum sensing to check if the primary network is idle or active. If the primary network is detected as idle, the secondary user can carry out data transmission. Spectrum sensing consumes energy and introduces false alarms and mis-detections. Given the delay cost associated with staying idle, the energy cost associated with spectrum sensing and data transmission, and the throughput gain associated with successful transmissions, the objective is to find an optimal sequence of idle/sensing actions, together with the optimal spectrum sensing durations, to maximize the expected net reward for the secondary user. We formulate this problem as a partially observable Markov decision process (POMDP) and obtain optimal control policies. Heuristic control policies that can be obtained at low complexity are also proposed.

Analytical formulations of dynamic spectrum access (DSA) with complete partitioning (CP), complete sharing (CS) and virtual partitioning (VP) for two radio systems are presented. The DSA with CP and CS models are solved explicitly using two one-dimensional Markov chains and a two-dimensional Markov chain, respectively, while the DSA with virtual partitioning model is solved numerically using a two-dimensional Markov chain. Grades of service (GoSs) like system airtime, blocking probabilities and preemption probabilities are considered. The performance of these GoS measures and the effect of the size of the nominal number of frequency channels for DSA with VP are evaluated. Numerical results illustrate that the advantages of DSA with VP as compared with DSA with CP and DSA with CS.

An analytical formulation of the saturated throughput of Prioritized Contention Access (PCA) with Hard Distributed Reservation Protocols (DRPs), Quiet Period (QP) and Beacon Period (BP) in Cognitive WiMedia MAC is presented. The analytical framework is formulated for one Hard DRP class and N PCA classes. The state transition diagram for the ith priority PCA class is modeled by a tri-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage, the second dimension is for the value of the backoff counter, while the third dimension is mainly for the delay due to DRP transmissions or QP and BP. A numerical result of the saturated throughput corresponding to typical parameter values is presented.

An analytical formulation of the saturated throughput of burst mode prioritized contention access (PCA) with hard distributed reservation protocols (DRPs) and beacon period (BP) in WiMedia MAC is presented. The analytical framework is formulated for one hard DRP class and N PCA classes. The state transition diagram for the ith priority PCA class is modeled by a tri-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage, the second dimension is for the value of the backoff counter, while the third dimension is mainly for the delay due to DRP transmissions or BP. The probability of the number of consecutive DRP MASs and the number of consecutive PCA MASs are derived, taking into consideration of all possible combinations of the DRP locations in a superframe. These probabilities are essential for the modeling of the Markov chain.

An analytical formulation of the saturated throughput of Prioritized Contention Access (PCA) with Hard Distributed Reservation Protocols (DRPs) and Beacon Period (BP) in the presence of bit error for WiMedia MAC is presented. The analytical framework is formulated for one Hard DRP class and N PCA classes. The state transition diagram for the ith priority PCA class is modeled by a tri-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage, the second dimension is for the value of the backoff counter, while the third dimension is mainly for the delay due to DRP transmissions or BP. Numerical results of the saturated throughput corresponding to data rate of 1 Gbps are presented.

An analytical formulation of the saturated throughput of a Cooperative MAC in IEEE 802.11n for multiclass traffic is presented. A helper node is used to relay packets from the source node or access point (AP) to the destination node within a circular coverage. The analytical framework is formulated for N classes, K data rates and their corresponding K distances. The saturated throughput analysis for multiclass traffic is formulated using a two- dimensional discrete-time Markov chain rather than using an approximation. The critical probability that a helper node exists in a region to relay a packet is explicitly derived. Closed-form result for the saturated delay is also derived. Numerical results of the saturated throughput corresponding to typical parameter values are presented. The results show that the total saturated throughput using Cooperative MAC can be better than that of IEEE 802.11n using direct transmissions by up to 67% and the saturated delays using Cooperative MAC are also better than those of IEEE 802.11n.

An analytical formulation of the saturated throughput of prioritized contention access (PCA) in the presence of hard and soft distributed reservation protocols (DRPs) and beacon period (BP) in WiMedia MAC is presented. The analytical framework is formulated for one Hard DRP class, one Soft DRP class and N PCA classes. The state transition diagram for the ith priority PCA class is modeled by a tri-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage, the second dimension is for the value of the backoff counter, while the third dimension is mainly for the delay due to DRP transmissions or BP. Numerical results of the saturated throughput corresponding to typical parameter values as well as for higher data rates are presented. A method to achieve higher saturated throughput in WiMedia MAC is also illustrated in the numerical results section.

Diabetic nephropathy (DN) remains a major complication in both type 1 and type 2 diabetes. Systemic administration of antitransforming growth factor-beta (TGF-beta) antibody has shown some promise in mouse models of DN. However, chronic blockade of the multifunctional TGB-beta could be problematic. Several downstream effects of TGF-beta are mediated by connective tissue growth factor (CTGF), which is up-regulated in several renal cells and secreted in the urine in the diabetic state. Using murine models of DN (type 1 and type 2) and a CTGF antisense oligonucleotide (ASO) of novel chimeric chemistry, we evaluated the specific role of this target in DN. In the type 1 model of DN, C57BL6 mice were made diabetic using streptozotocin injections and hyperglycemic animals were treated with CTGF ASOs (20 mg/kg/2 qw) for 4 months. ASO, but not mismatch control oligonucleotide, -treated animals showed significant reduction in target CTGF expression in the kidney with a concomitant decrease in proteinuria and albuminuria. Treatment with the CTGF ASO for 8 wk reduced serum creatinine and attenuated urinary albuminuria and proteinuria in diabetic db/db mice, a model of type 2 DN. The ASO also reduced expression of genes involved in matrix expansion such as fibronectin and collagen (I and IV) and an inhibitor of matrix degradation, PAI-1, in the renal cortex, contributing to significant reversal of mesangial expansion in both models of DN. Pathway analyses demonstrated that diabetes-induced phosphorylation of p38 MAPK and its downstream target CREB was also inhibited by the ASO. Our results strongly suggest that blocking CTGF using a chimeric ASO holds substantial promise for the treatment of DN.

ion and models to support formal methods Redundancy Management Systems Reconfiguration of the RTOS is a feature that has attracted a lot of attention. An optimized RTOS is clearly a very desirable objective, but the difficulty of certifying a system with this type of middleware is daunting. Exhaustive guarantees of assured safety under worst-case conditions are impossible. More limited guarantees are possible, which can be used to characterize the conditions under which sufficient confidence in the use of complex methods can be established. Future systems are likely to rely increasingly on dynamic reconfigurations to change the set of algorithms currently executing, and perhaps even the processors on which they are executing. The time frame

An analytical formulation of the saturated throughput of prioritized contention access (PCA) in the presence of hard distributed reservation protocols (DRPs) and beacon period (BP) in WiMedia MAC (formerly multi-band OFDM alliance (MBOA) MAC) is presented. The analytical framework is formulated for one hard DRP class and N PCA classes. The state transition diagram for the ith priority PCA class is modeled by a tri-dimensional discrete-time Markov chain. One dimension of the Markov chain is for the backoff stage, the second dimension is for the value of the backoff counter, while the third dimension is mainly for the delay due to DRP transmissions or BP. Numerical results of the saturated throughput corresponding to typical parameter values are presented.

The Th2 cytokines IL-4 and IL-13 mediate allergic pulmonary inflammation and airways hyperreactivity (AHR) in asthma models through signaling dependent upon the IL-4 receptor-alpha chain (IL-4Ralpha). IL-13 has been further implicated in the overproduction of mucus by the airway epithelium and in lung remodeling that commonly accompanies chronic inflammation. IL-4Ralpha-deficient mice are resistant to allergen-induced asthma, highlighting the therapeutic promise of selective molecular inhibitors of IL-4Ralpha. We designed a chemically modified IL-4Ralpha antisense oligonucleotide (IL-4Ralpha ASO) that specifically inhibits IL-4Ralpha protein expression in lung eosinophils, macrophages, dendritic cells, and airway epithelium after inhalation in allergen-challenged mice. Inhalation of IL-4Ralpha ASO attenuated allergen-induced AHR, suppressed airway eosinophilia and neutrophilia, and inhibited production of airway Th2 cytokines and chemokines in previously allergen-primed and -challenged mice. Histologic analysis of lungs from these animals demonstrated reduced goblet cell metaplasia and mucus staining that correlated with inhibition of Muc5AC gene expression in lung tissue. Therapeutic administration of inhaled IL-4Ralpha ASO in chronically allergen-challenged mice produced a spectrum of anti-inflammatory activity similar to that of systemically administered Dexamethasone with the added benefit of reduced airway neutrophilia. These data support the potential utility of a dual IL-4 and IL-13 oligonucleotide inhibitor in allergy/asthma, and suggest that local inhibition of IL-4Ralpha in the lung is sufficient to suppress allergen-induced pulmonary inflammation and AHR.

The capacity of a multi-time-hopping (MTH) binary pulse position modulation (PPM) ultra-wideband (UWB) system with Rake receivers and Gaussian monocycles supporting variable bit rate (VBR) multiclass services is presented. The analytical framework is formulated for the general case in which different traffic classes have different varying bit rates. The indoor channel model used is based on IEEE 802.15.3a. The analytical work leads to the determination of the system capacity of an MTH binary PPM UWB system with VBR traffic in an indoor multipath environment. Numerical results of the system capacity region are also presented.

We are designing and implementing an integrated programming framework to assist application program developers with the automation of a broad range of tasks. Our framework encourages the following activities: • analyzing the situation in which automation is going to be introduced, • capturing the results of the analysis as a model, • building a workflow application program to manage all of the activities, • configuring small collections of reuseable mechanisms to perform or assist with some of the activities, • customizing the configured mechanisms thus generating one or more application programs, • refining the resulting application programs on the basis of user reactions to them.

An analytical formulation of the outage probability in terms of bit error rate specification for variable bit rate (VBR) multiclass services in a multi-code direct-sequence ultra-wideband (DS-UWB) system with Rake receivers and Gaussian monocycles is presented. The analytical framework is first formulated for a single class traffic with continuous transmission and then generalized for different traffic classes with different varying bit rates. Multiple spreading codes are used by each user to achieve the varying video bit rate. The analytical work leads to the determination of the system capacity admission region of a multi-code DS-UWB system supporting VBR services in an indoor multipath environment. Numerical results of the admission regions demonstrate the differential performances under different channel model scenarios.